F.lux, popular Mac software that adjusts the color of your computer's display to adapt to the time of day, has been released for iPhone and iPad in beta outside of the App Store. The app can be downloaded and side-loaded on iOS 9 devices using Xcode 7 on a Mac running OS X 10.10 Yosemite or later.
F.lux will adjust your iPhone or iPad display to appear like sunlight during the day, and warm during nighttime hours to avoid looking at a bright screen. The app has settings to adjust the brightness level during the day and night, and you can also configure a time that you normally wake up each day.
Apple does not allow developers to access the Private APIs that f.lux requires to work on iOS, so the app is unlikely to appear on the App Store unless that policy changes. Since the app is side-loaded, there are no automatic updates, so the beta performs a daily update check and will display a message if a new version is available.
How to Sideload F.lux on iPhone and iPad
F.lux has provided step-by-step instructions on how to sideload the app on iPhone or iPad.
- Download and install Xcode 7 from the Mac App Store
- Download F.lux for iOS, unzip and open the “iflux.xcodeproj” project in Xcode
- Open Xcode > Preferences > Accounts and enter your iCloud or developer credentials
- Under Targets > iflux > General > Identity, give the Bundle Identifier a unique name
- Under the same Identity > Team menu, select your iCloud account or Developer profile
Next, connect your iPhone or iPad to a Mac using a Lightning cable and follow these steps:
- From the Xcode Product menu, choose Destination and select your iOS device
- Push Cmd-R when you’re ready to have f.lux
- When you first run, you’ll be prompted to open Settings > General > Profile on your device, and trust your developer account
- Run again, and allow location and notifications -- the app needs to be able to constantly communicate to run well